I have made a raised bed around 7 square meters around 10 inch deep. i have a lot of sieving to do using soil i took from my driveway will need to buy some top soil but i need to improve the soil i already have. so guys i was thinking of using a few bags of B&Q Horse Manure and possibly some bark if that's the correct stuff ta use? if i can use B&Q Horse Manure how many bags? anything else i can use? rather not waste my money doing this twice.